The New York Rangers would need to take on Schenn's full cap hit of $6.5M if they don't want to offer their first-round pick. But if they Rangers wanted the Blues to retain some salary, the price would certainly increase and would have to cost the Rangers a first-round pick.
Parssinen would be included as a replacement for Schenn in the Blues' lineup. However, Brett Berard, a solid prospect, could be one piece the Blues demand as the price for letting their captain go as the 22-year old is showing great promise.